1. Field of the Invention
This invention relates, in general, to a roadway reflector device for marking the lanes of a roadway or for use in constructing directional aids. More particularly, it relates to such a device which is substantially embedded below the grade of the roadway so as not to be damaged by, or to interfere with the movement of, oncoming traffic which passes over or upon the reflector device. Even more particularly, the invention relates to a roadway reflector device which gives way not only to a force directed downwardly on it but one also directed against it from the horizontal.
2. Description of the Prior Art
Roadway lane markers of the type that are embedded in the roadway and which, at least partially, project above the roadway surface, to indicate a traffic lane to a driver at night time, have been known now and, in some cases, used, for quite sometime. Such lane markers are more desirable than the usual painted dividing lines, not only because these markers, particularly if also reflective, are more visible to a driver over a greater distance than the usual white or yellow painted traffic lines but also because these devices, particularly those that are reflective, will function better in many instances where painted traffic lines are seen by a driver only with difficulty, or not at all, for example, as on wet roadways, or in cases of fog, or a newly snowplowed road, or in the light glare from oncoming vehicles. Nevertheless, though preferred to painted lane markers, the embedded reflective lane markers known about, and used heretofore, have not been without certain disadvantages.
One embedded lane marker used heretofore is shaped somewhat like a mushroom, the stem of that reflector device being located below the roadway surface with the reflective button on top thereof being mounted essentially at the surface of the roadway, to be visible to oncoming traffic. In some cases with such a lane marker device, the stem is capable of vertical up and down movement. Thus, when the tire of an oncoming vehicle passes over it, the marker is caused to move downwardly and offers little or no resistance to the impacting force, which resistance could result in damage to it. Nevertheless, in areas where the weather is cold, snow or ice sometimes packs around the stem, making it immovable against the force of impact and often resulting in a damaged reflector.
Although snow and ice packing around the stem of the just described lane marker device is a major problem source, another problem with such a device is that road debris, e.g., sand, and dirt, compacts around the stem, interfering with the device's ability to reciprocate vertically up and down. Thus, in that case, the so immobilized device offers resistance to an impacting force of a vehicle tire passing thereover and is, consequently, subjected to continuing damage.
The major shortcoming, however, of such a prior used lane marker device, at least in certain geographical areas, is the fact that it is capable only of vertical up and down movement. Thus, it gives way to a force exerted vertically downwardly on it, such as in the case of a vehicle tire passing over it. Nevertheless, it does not give way to a horizontally directed force, i.e., one directed at the reflector device from the side rather than essentially from the top. As a result, when the edge of the reflector button is hit just right by, for example, the blade of a snowplow, the lane marker device is damaged. In some cases, moreover, the reflective top is cut right off from the stem, or the entire device is ripped out of the roadbed.
When an embedded reflector device is damaged, or worse yet is ripped out of the roadway, there may be nothing then for some distance, to guide an oncoming motorist, leading to unsafe traffic conditions. This is a particular problem where two or more lane markers in a row are damaged, or missing. Thus, because of the damage caused to embedded lane marker devices, as abovedescribed, and the potential for such damage, from snowplows and the like which contact the device with a horizontally directed, impacting force, there has existed a continuing search over the years, for a better, and more enduring, roadway reflector device.
In U.S. Pat. No. 4,188,150, there is disclosed a lane marker of the embedded type which, contrary to the device described just above, and according to the patentee, is capable of giving way not only to a force directed vertically downwardly but also one horizontally from the side. In that device, a spherical member, or ball, mounted in a housing so as to project only partly above the roadway surface, is capable not only of rotational, but vertical up and down movement, as well. Thus, as claimed by the patentee, when a snowplow blade strikes the spherical member with an oncoming horizontally directed force, an upwardly directed vector of that force will cause the spherical member to rotate and a downwardly directed vector will push it downwardly against a spring. As a result, as can be inferred from the disclosure in that patent, as long as the spherical member is, and remains, freely rotatable, there should be no damage done by a snowplow to the lane marker, or at least less damage than in the case of the relatively inflexible reflective button device.
Nevertheless, a disadvantage in the lane marker device disclosed in U.S. Pat. No. 4,188,150, results from the fact that its freedom to freely rotate depends entirely upon the initial and continued frictional characteristics of the rotatable, spherical member, relative to the seat therefor. These relative frictional characteristics can be affected considerably and disadvantageously in use, as in the case of the first previously disclosed, earlier used reflector device, due not only to snow and ice but, in particular, to sand, dirt, and other debris coming between the rotatable spherical member and its seat. In the worst case, the spherical member will no longer rotate and like the reflective button, as in the device earlier disclosed, when hit by a snow plow blade edge, because of its inability to rotate, can become damaged.
Furthermore, it is not clear from the disclosure in U.S. Pat. No. 4,188,150, whether the ball is of a plastic composition which contains colored materials such as a phosphorescent, which imparts to the ball its orange color, or the surface of the ball is merely colored with such a material. Nevertheless, the ball does not appear to have reflective characteristics.
Another lane marker of the type in which a rotatable spherical element is provided, located in a socket therefor, and which projects in part above the roadway surface, is disclosed in U.S. Pat. No. 4,234,264. In that device, however, the rotatable spherical element rather than being capable of vertical up and down movement, as well as being rotatable, is deformable, instead. Thus, according to the patentee, when impacted by a force, the impacting force is nullified, as that force causes the sphere to be initially deformed and, if the impacting force is excessive, the sphere then is caused by that force to rotate in its supporting socket. The sphere disclosed in U.S. Pat. No. 4,234,264 is hollow, and transparent, and includes, within it a reflective body which floats in a fluid. The reflective body has in the bottom thereof a magnet attractable by another magnet located at the bottom of the socket for the rotatable sphere.
Normally, the attraction of the magnets for one another causes the flotable reflective member to maintain the reflective portion thereof in an upright position whereby to be picked up by the lights of vehicles of oncoming motorists, and reflected back. When a force impacts the spherical member, e.g., the tire of a moving automobile, it deforms, and the force attracting the two magnets together is overcome at the same time. Thus, this lane marker, in accordance with what can be inferred from the patent, gives way to any potentially damaging force, whatever it may be, whether directed downwardly or from the side. When the impacting force passes by the lane marker, according to the patentee, the hollow, temporarily deformed sphere resumes its spherical shape, as a result of the reflective member realigning itself due to the attraction of the magnets one for the other. The spherical member is mounted to snugly fit in the socket therefor, whereby, according to the patentee, to prevent liquid or any foreign matter from affecting its operation. Nevertheless, this lane marking device, like that in U.S. Pat. No. 4,188,150, depends for its continued good operation substantially on the free rotation of the spherical member in its socket and that free rotation depends, in turn, upon the frictional characteristics of the sphere relative to the socket. It also depends for continued good functioning on the integrity of the material of the deformable spherical member, when subjected to great force of impact by, e.g., the edge of a snowplow blade.